The use of computers in today's business operations has created two related problems associates with the tape cartridges used with the computers. The first problem relates to a storage system which is readily accessible so that tape cartridges can be removed from or returned to the storage system. There are commercially available trucks which are provided with means for holding a plurality of tape cartridges and which are provided with wheels for easy movement thereof. The trucks may be moved into the tape cartridge storage system, tape cartridges removed from the storage system and transported to the computer for use and then returned to the tape cartridge storage system. With the ever increasing cost of floor space, it is necessary and desirable that the aisle space in a tape cartridge storage system be kept to a minimum. This has resulted in limiting the size of the trucks used in transporting the tape cartridges and also in limiting the number of tape cartridges that can be loaded onto the truck.